1. Field of the Invention
As is known, articulated power driven vehicles are used as tractors or prime movers in the earth-moving industry and agriculture. They comprise a front frame structure and a rear frame structure interconnected by a hinge unit which permits mutual pivotal movements of the interconnected parts for relative steering articulation about a substantially vertical axis and a relative oscillation about a substantially horizontal axis. Each frame structure is equipped with non-dirigibly mounted ground-engaging wheels and both or one of them may have power plants mounted thereon which are connected through a power train to the wheels of the vehicle. The latter is steered by means of steering jacks in the form of hydraulic rams mounted on the front frame structure and acting on the rear one. Such articulated power vehicles are described in U.S. Pat. No. 3,157,239 which is hereby incorporated by reference.
2. Description of the Prior Art
In known vehicles of this type the hinge unit which connects or suspends adjacent ends of the two frame structures, has some adverse effect upon operation of the vehicle in that mutual angular displacements around a horizontal axis in connection with mutual angular displacements around a vertical axis due to steering operations and articulations generate forces, the action lines of which lie in different planes and point in different directions, especially if both frame structures are equipped with individual power plants. Moreover, the forces may have vertical components which would entail an uneven distribution of weight on and, thereby, spinning of the ground-engaging wheels.